The present invention relates to an overhead stowage system for airplanes and particularly to such a system which is easier for flight personnel and passengers to operate.
Public transportation vehicles are typically provided with stowage facilities proximate passenger seats where passengers may stow personal luggage during travel. Airplanes, for example, have closable stowage bins located above the passenger seats for securing personal belongings even during turbulent travel conditions.
The center overhead stowage bins of an airplane are located with sufficient head room above the center row seats of the airplane so that when the bins are in their retracted position, passengers may access the seats therebelow. A movable holding bin of a center overhead stowage bin typically has a down, open position which is lower than the retracted, closed position in order to permit easy access during loading and unloading. After loading the bin, a passenger or flight attendant lifts the bin from its down, open position up to its retracted, closed position.
Center overhead stowage bins usually comprise a support structure fixed to the interior ceiling supports of the airplane's passenger compartment, the support structure consisting of a rectangular box frame. The holding bin which is tiltable fits within the open bottom of the support structure box frame, the bin being guided within the support structure by linkage arms. The linkage arms are pivotally mounted between the holding bin and the support structure and have different lengths so that, when the holding bin is moved downwardly with respect to the support structure, the bin tilts as it pivotally drops into its lower, open position. When the holding bin is returned to its retracted, closed position, a latch engages a protruding post on the support structure for securing the bin in its closed position.
Passive springs and snubbers may accompany the linkage arms to assist lifting and lowering the holding bin relative the support structure. Passive springs, e.g. hydraulic springs, operate between the support structure and the linkage arms whereby the holding bin receives an upward force for assisting an operator in moving the bin within its designated path. The snubbers are coupled between the linkage arms and the support structure. When the latch is released for lowering the holding bin, the snubbers limit how fast the holding bin falls into its lower, open position.
The above-described overhead stowage bins require an operator to provide manual force comparable to the luggage weight (minus the passive spring forces as delivered via the linkage arms) in order to push the loaded bin up from its open position to its closed position. Therefore, bin size has been kept small in order to limit the quantity of luggage the bin can hold and thus limit its load weight in accordance with the force considered appropriate for a passenger or flight attendant to exert. Even then, difficulty may be experienced by passengers in properly loading luggage. For instance, if a passive bin design provides 80 pounds of lifting force for lifting 20 pounds of luggage, then the passenger will likewise have to overcome the 80 pound lifting force in order to pull the bin down when empty.